ref: d2333a90c9eed0be38d722bfcd0d8b5dee0e56a7
dir: /audio/engine.asm/
; The entire sound engine. Uses section "audio" in WRAM. ; Interfaces are in bank 0. ; Notable functions: ; UpdateSound (called during VBlank) ; FadeMusic ; PlaySFX ; PlayCry SoundRestart: ; e8000 ; restart sound operation ; clear all relevant hardware registers & wram push hl push de push bc push af call MusicOff ld hl, rNR50 ; channel control registers xor a ld [hli], a ; rNR50 ; volume/vin ld [hli], a ; rNR51 ; sfx channels ld a, $80 ; all channels on ld [hli], a ; ff26 ; music channels ld hl, rNR10 ; sound channel registers ld e, $04 ; number of channels .clearsound ; sound channel 1 2 3 4 xor a ld [hli], a ; rNR10, $ff15, rNR30, $ff1f ; sweep = 0 ld [hli], a ; rNR11, rNR21, rNR31, rNR41 ; length/wavepattern = 0 ld a, $08 ld [hli], a ; rNR12, rNR22, rNR32, rNR42 ; envelope = 0 xor a ld [hli], a ; rNR13, rNR23, rNR33, rNR43 ; frequency lo = 0 ld a, $80 ld [hli], a ; rNR14, rNR24, rNR34, rNR44 ; restart sound (freq hi = 0) dec e jr nz, .clearsound ld hl, Channel1 ; start of channel data ld de, $01bf ; length of area to clear (entire sound wram area) .clearchannels ; clear $c101-$c2bf xor a ld [hli], a dec de ld a, e or d jr nz, .clearchannels ld a, $77 ; max ld [Volume], a call MusicOn pop af pop bc pop de pop hl ret ; e803d MusicFadeRestart: ; e803d ; restart but keep the music id to fade in to ld a, [MusicFadeIDHi] push af ld a, [MusicFadeIDLo] push af call SoundRestart pop af ld [MusicFadeIDLo], a pop af ld [MusicFadeIDHi], a ret ; e8051 MusicOn: ; e8051 ld a, $01 ld [MusicPlaying], a ret ; e8057 MusicOff: ; e8057 xor a ld [MusicPlaying], a ret ; e805c UpdateSound: ; e805c ; called once per frame ; no use updating audio if it's not playing ld a, [MusicPlaying] and a ret z ; start at ch1 xor a ld [CurChannel], a ; just ld [SoundOutput], a ; off ld bc, Channel1 .loop ; is the channel active? ld hl, Channel1Flags - Channel1 add hl, bc bit 0, [hl] jp z, .nextchannel ; check time left in the current note ld hl, Channel1NoteDuration - Channel1 add hl, bc ld a, [hl] cp a, $02 ; 1 or 0? jr c, .noteover dec [hl] jr .asm_e8093 .noteover ; reset vibrato delay ld hl, Channel1VibratoDelay - Channel1 add hl, bc ld a, [hl] ld hl, Channel1VibratoDelayCount - Channel1 add hl, bc ld [hl], a ; turn vibrato off for now ld hl, Channel1Flags2 - Channel1 add hl, bc res 1, [hl] ; get next note call ParseMusic .asm_e8093 ; call Functione84f9 ; duty cycle ld hl, Channel1DutyCycle - Channel1 add hl, bc ld a, [hli] ld [$c292], a ; intensity ld a, [hli] ld [$c293], a ; frequency ld a, [hli] ld [$c294], a ld a, [hl] ld [$c295], a ; call Functione8466 ; handle vibrato and other things call HandleNoise ; turn off music when playing sfx? ld a, [SFXPriority] and a jr z, .next ; are we in a sfx channel right now? ld a, [CurChannel] cp a, $04 jr nc, .next ; are any sfx channels active? ; if so, mute ld hl, $c1cc ; Channel5Flags bit 0, [hl] jr nz, .restnote ld hl, $c1fe ; Channel6Flags bit 0, [hl] jr nz, .restnote ld hl, $c230 ; Channel7Flags bit 0, [hl] jr nz, .restnote ld hl, $c262 ; Channel8Flags bit 0, [hl] jr z, .next .restnote ld hl, Channel1NoteFlags - Channel1 add hl, bc set 5, [hl] ; Rest .next ; are we in a sfx channel right now? ld a, [CurChannel] cp a, $04 ; sfx jr nc, .asm_e80ee ld hl, $00cb add hl, bc bit 0, [hl] jr nz, .asm_e80fc .asm_e80ee call UpdateChannels ld hl, Channel1Tracks - Channel1 add hl, bc ld a, [SoundOutput] or [hl] ld [SoundOutput], a .asm_e80fc ; clear note flags ld hl, Channel1NoteFlags - Channel1 add hl, bc xor a ld [hl], a .nextchannel ; next channel ld hl, Channel2 - Channel1 add hl, bc ld c, l ld b, h ld a, [CurChannel] inc a ld [CurChannel], a cp a, $08 ; are we done? jp nz, .loop ; do it all again ; writing to hardware registers? call Functione8307 ; fade music in/out call FadeMusic ; write volume to hardware register ld a, [Volume] ld [rNR50], a ; write SO on/off to hardware register ld a, [SoundOutput] ld [rNR51], a ret ; e8125 UpdateChannels: ; e8125 ld hl, .ChannelFnPtrs ld a, [CurChannel] and a, $07 add a ld e, a ld d, $00 add hl, de ld a, [hli] ld h, [hl] ld l, a jp [hl] .ChannelFnPtrs dw .Channel1 dw .Channel2 dw .Channel3 dw .Channel4 ; sfx ch ptrs are identical to music chs ; ..except 5 dw .Channel5 dw .Channel6 dw .Channel7 dw .Channel8 .Channel1 ld a, [$c2a6] bit 7, a ret nz .Channel5 ld hl, Channel1NoteFlags - Channel1 add hl, bc bit 3, [hl] jr z, .asm_e8159 ; ld a, [SoundInput] ld [rNR10], a .asm_e8159 bit 5, [hl] ; rest jr nz, .ch1rest bit 4, [hl] jr nz, .asm_e81a2 bit 1, [hl] jr nz, .asm_e816b bit 6, [hl] jr nz, .asm_e8184 jr .asm_e8175 .asm_e816b ld a, [$c294] ld [rNR13], a ld a, [$c295] ld [rNR14], a .asm_e8175 bit 0, [hl] ret z ld a, [$c292] ld d, a ld a, [rNR11] and a, $3f ; sound length or d ld [rNR11], a ret .asm_e8184 ld a, [$c292] ld d, a ld a, [rNR11] and a, $3f ; sound length or d ld [rNR11], a ld a, [$c294] ld [rNR13], a ret .ch1rest ld a, [rNR52] and a, %10001110 ; ch1 off ld [rNR52], a ld hl, rNR10 call ClearChannel ret .asm_e81a2 ld hl, $c292 ld a, $3f ; sound length or [hl] ld [rNR11], a ld a, [$c293] ld [rNR12], a ld a, [$c294] ld [rNR13], a ld a, [$c295] or a, $80 ld [rNR14], a ret .Channel2 .Channel6 ld hl, Channel1NoteFlags - Channel1 add hl, bc bit 5, [hl] ; rest jr nz, .ch2rest bit 4, [hl] jr nz, .asm_e8204 bit 6, [hl] jr nz, .asm_e81e6 bit 0, [hl] ret z ld a, [$c292] ld d, a ld a, [rNR21] and a, $3f ; sound length or d ld [rNR21], a ret .asm_e81db ; unused ld a, [$c294] ld [rNR23], a ld a, [$c295] ld [rNR24], a ret .asm_e81e6 ld a, [$c292] ld d, a ld a, [rNR21] and a, $3f ; sound length or d ld [rNR21], a ld a, [$c294] ld [rNR23], a ret .ch2rest ld a, [rNR52] and a, %10001101 ; ch2 off ld [rNR52], a ld hl, $ff15 call ClearChannel ret .asm_e8204 ld hl, $c292 ld a, $3f ; sound length or [hl] ld [rNR21], a ld a, [$c293] ld [rNR22], a ld a, [$c294] ld [rNR23], a ld a, [$c295] or a, $80 ; initial (restart) ld [rNR24], a ret .Channel3 .Channel7 ld hl, Channel1NoteFlags - Channel1 add hl, bc bit 5, [hl] ; rest jr nz, .ch3rest bit 4, [hl] jr nz, .asm_e824d bit 6, [hl] jr nz, .asm_e823a ret .asm_e822f ; unused ld a, [$c294] ld [rNR33], a ld a, [$c295] ld [rNR34], a ret .asm_e823a ld a, [$c294] ld [rNR33], a ret .ch3rest ld a, [rNR52] and a, %10001011 ; ch3 off ld [rNR52], a ld hl, rNR30 call ClearChannel ret .asm_e824d ld a, $3f ld [rNR31], a xor a ld [rNR30], a call .asm_e8268 ld a, $80 ld [rNR30], a ld a, [$c294] ld [rNR33], a ld a, [$c295] or a, $80 ld [rNR34], a ret .asm_e8268 push hl ld a, [$c293] and a, $0f ; only 0-9 are valid ld l, a ld h, $00 ; hl << 4 ; each wavepattern is $0f bytes long ; so seeking is done in $10s add hl, hl add hl, hl add hl, hl add hl, hl ld de, WaveSamples add hl, de ; load wavepattern into $ff30-$ff3f ld a, [hli] ld [$ff30], a ld a, [hli] ld [$ff31], a ld a, [hli] ld [$ff32], a ld a, [hli] ld [$ff33], a ld a, [hli] ld [$ff34], a ld a, [hli] ld [$ff35], a ld a, [hli] ld [$ff36], a ld a, [hli] ld [$ff37], a ld a, [hli] ld [$ff38], a ld a, [hli] ld [$ff39], a ld a, [hli] ld [$ff3a], a ld a, [hli] ld [$ff3b], a ld a, [hli] ld [$ff3c], a ld a, [hli] ld [$ff3d], a ld a, [hli] ld [$ff3e], a ld a, [hli] ld [$ff3f], a pop hl ld a, [$c293] and a, $f0 sla a ld [rNR32], a ret .Channel4 .Channel8 ld hl, Channel1NoteFlags - Channel1 add hl, bc bit 5, [hl] ; rest jr nz, .ch4rest bit 4, [hl] jr nz, .asm_e82d4 ret .asm_e82c1 ; unused ld a, [$c294] ld [rNR43], a ret .ch4rest ld a, [rNR52] and a, %10000111 ; ch4 off ld [rNR52], a ld hl, $ff1f call ClearChannel ret .asm_e82d4 ld a, $3f ; sound length ld [rNR41], a ld a, [$c293] ld [rNR42], a ld a, [$c294] ld [rNR43], a ld a, $80 ld [rNR44], a ret ; e82e7 _CheckSFX: ; e82e7 ; return carry if any sfx channels are active ld hl, $c1cc ; Channel5Flags bit 0, [hl] jr nz, .sfxon ld hl, $c1fe ; Channel6Flags bit 0, [hl] jr nz, .sfxon ld hl, $c230 ; Channel7Flags bit 0, [hl] jr nz, .sfxon ld hl, $c262 ; Channel8Flags bit 0, [hl] jr nz, .sfxon and a ret .sfxon scf ret ; e8307 Functione8307: ; e8307 ; what is $c2a6? ld a, [$c2a6] bit 7, a ret z and a, $7f ld d, a call _CheckSFX jr c, .asm_e8335 and a jr z, .asm_e8323 cp a, $10 jr z, .asm_e831e jr .asm_e8335 .asm_e831e ld hl, Tablee8354 jr .updatehw .asm_e8323 ld hl, Tablee8350 .updatehw xor a ld [rNR10], a ; sweep off ld a, [hli] ld [rNR11], a ; sound length / duty cycle ld a, [hli] ld [rNR12], a ; ch1 volume envelope ld a, [hli] ld [rNR13], a ; ch1 frequency lo ld a, [hli] ld [rNR14], a ; ch1 frequency hi .asm_e8335 ld a, d inc a cp a, $1e jr c, .asm_e833c xor a .asm_e833c or a, $80 ld [$c2a6], a ; is hw ch1 on? ld a, [SoundOutput] and a, $11 ret nz ; if not, turn it on ld a, [SoundOutput] or a, $11 ld [SoundOutput], a ret ; e8350 Tablee8350: ; e8350 db $80 ; duty 50% db $e2 ; volume $e, envelope decrease sweep 2 db $50 ; frequency: $750 db $87 ; restart sound ; e8354 Tablee8354: ; e8354 db $80 ; duty 50% db $e2 ; volume $e, envelope decrease sweep 2 db $ee ; frequency: $6ee db $86 ; restart sound ; e8358 FadeMusic: ; e8358 ; fade music if applicable ; usage: ; write to MusicFade ; song fades out at the given rate ; load song id in MusicFadeID ; fade new song in ; notes: ; max # frames per volume level is $3f ; fading? ld a, [MusicFade] and a ret z ; has the count ended? ld a, [MusicFadeCount] and a jr z, .update ; count down dec a ld [MusicFadeCount], a ret .update ld a, [MusicFade] ld d, a ; get new count and a, $3f ld [MusicFadeCount], a ; get SO1 volume ld a, [Volume] and a, $07 ; which way are we fading? bit 7, d jr nz, .fadein ; fading out and a jr z, .novolume dec a jr .updatevolume .novolume ; make sure volume is off xor a ld [Volume], a ; did we just get on a bike? ld a, [PlayerState] cp a, $01 ; bicycle jr z, .bicycle push bc ; restart sound call MusicFadeRestart ; get new song id ld a, [MusicFadeIDLo] and a jr z, .quit ; this assumes there are fewer than 256 songs! ld e, a ld a, [MusicFadeIDHi] ld d, a ; load new song call LoadMusic .quit ; cleanup pop bc ; stop fading xor a ld [MusicFade], a ret .bicycle push bc ; restart sound call MusicFadeRestart ; this turns the volume up ; turn it back down xor a ld [Volume], a ; get new song id ld a, [MusicFadeIDLo] ld e, a ld a, [MusicFadeIDHi] ld d, a ; load new song call LoadMusic pop bc ; fade in ld hl, MusicFade set 7, [hl] ret .fadein ; are we done? cp a, $07 jr nc, .maxvolume ; inc volume inc a jr .updatevolume .maxvolume ; we're done xor a ld [MusicFade], a ret .updatevolume ; hi = lo ld d, a swap a or d ld [Volume], a ret ; e83d1 LoadNote: ; e83d1 ; check mute?? ld hl, Channel1Flags2 - Channel1 add hl, bc bit 1, [hl] ret z ; get note duration ld hl, Channel1NoteDuration - Channel1 add hl, bc ld a, [hl] ld hl, $c297 ; ???? sub [hl] jr nc, .ok ld a, $01 .ok ld [hl], a ; get frequency ld hl, Channel1Frequency - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ; ???? ld hl, $0021 add hl, bc ld a, e sub [hl] ld e, a ld a, d sbc a, $00 ld d, a ; ???? ld hl, $0022 add hl, bc sub [hl] jr nc, .asm_e8420 ; ???? ld hl, Channel1Flags3 - Channel1 add hl, bc set 1, [hl] ; get frequency ld hl, Channel1Frequency - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ; ???? ld hl, $0021 add hl, bc ld a, [hl] sub e ld e, a ld a, d sbc a, $00 ld d, a ; ???? ld hl, $0022 add hl, bc ld a, [hl] sub d ld d, a jr .asm_e843e .asm_e8420 ; ???? ld hl, Channel1Flags3 - Channel1 add hl, bc res 1, [hl] ; get frequency ld hl, Channel1Frequency - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ; ???? ld hl, $0021 add hl, bc ld a, e sub [hl] ld e, a ld a, d sbc a, $00 ld d, a ; ???? ld hl, $0022 add hl, bc sub [hl] ld d, a .asm_e843e push bc ld hl, $c297 ld b, $00 ; loop count .loop inc b ld a, e sub [hl] ld e, a jr nc, .loop ld a, d and a jr z, .quit dec d jr .loop .quit ld a, e ; result add [hl] ld d, b ; loop count ; ???? pop bc ld hl, $0023 add hl, bc ld [hl], d ld hl, $0024 add hl, bc ld [hl], a ; clear ???? ld hl, $0025 add hl, bc xor a ld [hl], a ret ; e8466 Functione8466: ; e8466 ; handle vibrato and other things ; unknowns: $c292, $c294 ld hl, Channel1Flags2 - Channel1 add hl, bc bit 2, [hl] jr z, .next ld hl, $001c add hl, bc ld a, [hl] rlca rlca ld [hl], a and a, $c0 ld [$c292], a ld hl, Channel1NoteFlags - Channel1 add hl, bc set 0, [hl] .next ld hl, Channel1Flags2 - Channel1 add hl, bc bit 4, [hl] jr z, .vibrato ld hl, $0027 add hl, bc ld e, [hl] inc hl ld d, [hl] ld hl, $c294 ld a, [hli] ld h, [hl] ld l, a add hl, de ld e, l ld d, h ld hl, $c294 ld [hl], e inc hl ld [hl], d .vibrato ; is vibrato on? ld hl, Channel1Flags2 - Channel1 add hl, bc bit 0, [hl] ; vibrato jr z, .quit ; is vibrato active for this note yet? ; is the delay over? ld hl, Channel1VibratoDelayCount - Channel1 add hl, bc ld a, [hl] and a jr nz, .subexit ; is the extent nonzero? ld hl, Channel1VibratoExtent - Channel1 add hl, bc ld a, [hl] and a jr z, .quit ; save it for later ld d, a ; is it time to toggle vibrato up/down? ld hl, Channel1VibratoRate - Channel1 add hl, bc ld a, [hl] and a, $0f ; count jr z, .toggle .subexit dec [hl] jr .quit .toggle ; refresh count ld a, [hl] swap [hl] or [hl] ld [hl], a ; ???? ld a, [$c294] ld e, a ; toggle vibrato up/down ld hl, Channel1Flags3 - Channel1 add hl, bc bit 0, [hl] ; vibrato up/down jr z, .down ; up ; vibrato down res 0, [hl] ; get the delay ld a, d and a, $0f ; lo ; ld d, a ld a, e sub d jr nc, .asm_e84ef ld a, $00 jr .asm_e84ef .down ; vibrato up set 0, [hl] ; get the delay ld a, d and a, $f0 ; hi swap a ; move it to lo ; add e jr nc, .asm_e84ef ld a, $ff .asm_e84ef ld [$c294], a ; ld hl, Channel1NoteFlags - Channel1 add hl, bc set 6, [hl] .quit ret ; e84f9 Functione84f9: ; e84f9 ; quit if ???? ld hl, Channel1Flags2 - Channel1 add hl, bc bit 1, [hl] ret z ; de = Frequency ld hl, Channel1Frequency - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ; ld hl, Channel1Flags3 - Channel1 add hl, bc bit 1, [hl] jr z, .next ; ld hl, $0023 add hl, bc ld l, [hl] ld h, $00 add hl, de ld d, h ld e, l ; get ???? ld hl, $0024 add hl, bc ld a, [hl] ; add it to ???? ld hl, $0025 add hl, bc add [hl] ld [hl], a ld a, $00 adc e ld e, a ld a, $00 adc d ld d, a ; ld hl, $0022 add hl, bc ld a, [hl] cp d jp c, .quit1 jr nz, .quit2 ld hl, $0021 add hl, bc ld a, [hl] cp e jp c, .quit1 jr .quit2 .next ld a, e ld hl, $0023 add hl, bc ld e, [hl] sub e ld e, a ld a, d sbc a, $00 ld d, a ld hl, $0024 add hl, bc ld a, [hl] add a ld [hl], a ld a, e sbc a, $00 ld e, a ld a, d sbc a, $00 ld d,a ld hl, $0022 add hl, bc ld a, d cp [hl] jr c, .quit1 jr nz, .quit2 ld hl, $0021 add hl, bc ld a, e cp [hl] jr nc, .quit2 .quit1 ld hl, Channel1Flags2 - Channel1 add hl, bc res 1, [hl] ld hl, Channel1Flags3 - Channel1 add hl, bc res 1, [hl] ret .quit2 ld hl, Channel1Frequency - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ld hl, Channel1NoteFlags - Channel1 add hl, bc set 1, [hl] set 0, [hl] ret ; e858c HandleNoise: ; e858c ; is noise sampling on? ld hl, Channel1Flags - Channel1 add hl, bc bit 4, [hl] ; noise sampling ret z ; are we in a sfx channel? ld a, [CurChannel] bit 2, a ; sfx jr nz, .next ; is ch8 on? (noise) ld hl, $c262 ; Channel8Flags bit 0, [hl] ; on? jr z, .next ; is ch8 playing noise? bit 4, [hl] ret nz ; quit if so ; .next ld a, [$c2a2] and a jr z, ReadNoiseSample dec a ld [$c2a2], a ret ; e85af ReadNoiseSample: ; e85af ; sample struct: ; [wx] [yy] [zz] ; w: ? either 2 or 3 ; x: ? 0-7 ; zzyy: pointer to sample data ; NOTE: these seem to have $4000 added to them later ; de = NoiseSampleAddress ld hl, NoiseSampleAddress ld e, [hl] inc hl ld d, [hl] ; is it empty? ld a, e or d jr z, .quit ; get the noise sample ld a, [de] inc de ; are we done? cp a, $ff jr z, .quit ; and a, $0f ; bottom nybble inc a ld [$c2a2], a ld a, [de] inc de ld [$c293], a ld a, [de] inc de ld [$c294], a xor a ld [$c295], a ; ld hl, NoiseSampleAddress ld [hl], e inc hl ld [hl], d ld hl, Channel1NoteFlags - Channel1 add hl, bc set 4, [hl] ret .quit ret ; e85e1 ParseMusic: ; e85e1 ; parses until a note is read or the song is ended call GetMusicByte ; store next byte in a cp a, $ff ; is the song over? jr z, .readff cp a, $d0 ; is it a note? jr c, .readnote ; then it's a command .readcommand call ParseCommand jr ParseMusic ; start over .readnote ; CurMusicByte contains current note ; special notes ld hl, Channel1Flags - Channel1 add hl, bc bit 3, [hl] jp nz, Functione8698 bit 5, [hl] jp nz, Functione8698 bit 4, [hl] ; noise sample jp nz, GetNoiseSample ; normal note ; set note duration (bottom nybble) ld a, [CurMusicByte] and a, $0f call SetNoteDuration ; get note pitch (top nybble) ld a, [CurMusicByte] swap a and a, $0f jr z, .rest ; pitch $0 -> rest ; update pitch ld hl, Channel1Pitch - Channel1 add hl, bc ld [hl], a ; store pitch in e ld e, a ; store octave in d ld hl, Channel1Octave - Channel1 add hl, bc ld d, [hl] ; update frequency call GetFrequency ld hl, Channel1Frequency - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ; ???? ld hl, Channel1NoteFlags - Channel1 add hl, bc set 4, [hl] jp LoadNote .rest ; note = rest ld hl, Channel1NoteFlags - Channel1 add hl, bc set 5, [hl] ; Rest ret ; .readff ; $ff is reached in music data ld hl, Channel1Flags - Channel1 add hl, bc bit 1, [hl] ; in a subroutine? jr nz, .readcommand ; execute ld a, [CurChannel] cp a, $04 ; channels 0-3? jr nc, .asm_e8651 ; ???? ld hl, $00cb add hl, bc bit 0, [hl] jr nz, .ok .asm_e8651 ld hl, Channel1Flags - Channel1 add hl, bc bit 5, [hl] call nz, RestoreVolume ; end music ld a, [CurChannel] cp a, $04 ; channel 5? jr nz, .ok ; ???? xor a ld [rNR10], a ; sweep = 0 .ok ; stop playing ; turn channel off ld hl, Channel1Flags - Channel1 add hl, bc res 0, [hl] ; note = rest ld hl, Channel1NoteFlags - Channel1 add hl, bc set 5, [hl] ; clear music id & bank ld hl, Channel1MusicID - Channel1 add hl, bc xor a ld [hli], a ; id hi ld [hli], a ; id lo ld [hli], a ; bank ret ; e8679 RestoreVolume: ; e8679 ; ch5 only ld a, [CurChannel] cp a, $04 ret nz xor a ld hl, $c222 ld [hli], a ld [hl], a ld hl, $c286 ld [hli], a ld [hl], a ld a, [LastVolume] ld [Volume], a xor a ld [LastVolume], a ld [SFXPriority], a ret ; e8698 Functione8698: ; e8698 ; turn noise sampling on ld hl, Channel1NoteFlags - Channel1 add hl, bc set 4, [hl] ; noise sample ; update note duration ld a, [CurMusicByte] call SetNoteDuration ; top nybble doesnt matter? ; update intensity from next param call GetMusicByte ld hl, Channel1Intensity - Channel1 add hl, bc ld [hl], a ; update lo frequency from next param call GetMusicByte ld hl, Channel1FrequencyLo - Channel1 add hl, bc ld [hl], a ; are we on the last channel? (noise sampling) ld a, [CurChannel] and a, $03 cp a, $03 ret z ; update hi frequency from next param call GetMusicByte ld hl, Channel1FrequencyHi - Channel1 add hl, bc ld [hl], a ret ; e86c5 GetNoiseSample: ; e86c5 ; load ptr to sample header in NoiseSampleAddress ; are we on the last channel? ld a, [CurChannel] and a, $03 cp a, $03 ; ret if not ret nz ; update note duration ld a, [CurMusicByte] and a, $0f call SetNoteDuration ; check current channel ld a, [CurChannel] bit 2, a ; are we in a sfx channel? jr nz, .sfx ld hl, $c262 ; Channel8Flags bit 0, [hl] ; is ch8 on? (noise) ret nz ld a, [MusicNoiseSampleSet] jr .next .sfx ld a, [SFXNoiseSampleSet] .next ; load noise sample set id into de ld e, a ld d, $00 ; load ptr to noise sample set in hl ld hl, NoiseSampleSetsPointers add hl, de add hl, de ld a, [hli] ld h, [hl] ld l, a ; get pitch ld a, [CurMusicByte] swap a ; non-rest note? and a, $0f ret z ; use 'pitch' to seek noise sample set ld e, a ld d, $00 add hl, de add hl, de ; load sample pointer into NoiseSampleAddress ld a, [hli] ld [NoiseSampleAddressLo], a ld a, [hl] ld [NoiseSampleAddressHi], a ; clear ???? xor a ld [$c2a2], a ret ; e870f ParseCommand ; e870f ; reload command ld a, [CurMusicByte] ; get command # sub a, $d0 ; first command ld e, a ld d, $00 ; seek command pointer ld hl, MusicCommands add hl, de add hl, de ; jump to the new pointer ld a, [hli] ld h, [hl] ld l, a jp [hl] ; e8720 MusicCommands: ; e8720 ; pointer to each command in order ; octaves dw MusicD0 ; octave 8 dw MusicD0 ; octave 7 dw MusicD0 ; octave 6 dw MusicD0 ; octave 5 dw MusicD0 ; octave 4 dw MusicD0 ; octave 3 dw MusicD0 ; octave 2 dw MusicD0 ; octave 1 dw MusicD8 ; note length + intensity dw MusicD9 ; set starting octave dw MusicDA ; tempo dw MusicDB ; duty cycle dw MusicDC ; intensity dw MusicDD ; update sound status dw MusicDE ; ???? + duty cycle dw MusicDF ; dw MusicE0 ; dw MusicE1 ; vibrato dw MusicE2 ; dw MusicE3 ; music noise sampling dw MusicE4 ; force panning dw MusicE5 ; volume dw MusicE6 ; tune dw MusicE7 ; dw MusicE8 ; dw MusicE9 ; global tempo dw MusicEA ; restart current channel from header dw MusicEB ; new song dw MusicEC ; sfx priority on dw MusicED ; sfx priority off dw MusicEE ; dw MusicEF ; stereo panning dw MusicF0 ; sfx noise sampling dw MusicF1 ; nothing dw MusicF1 ; nothing dw MusicF1 ; nothing dw MusicF1 ; nothing dw MusicF1 ; nothing dw MusicF1 ; nothing dw MusicF1 ; nothing dw MusicF1 ; nothing dw MusicF9 ; dw MusicFA ; dw MusicFB ; dw MusicFC ; jump dw MusicFD ; loop dw MusicFE ; call dw MusicFF ; return ; e8780 MusicF1: ; e8780 ret ; e8781 MusicFF: ; e8781 ; called when $ff is encountered w/ subroutine flag set ; end music stream ; return to caller of the subroutine ; reset subroutine flag ld hl, Channel1Flags - Channel1 add hl, bc res 1, [hl] ; copy LastMusicAddress to MusicAddress ld hl, Channel1LastMusicAddress - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ld hl, Channel1MusicAddress - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ret ; e8796 MusicFE: ; e8796 ; call music stream (subroutine) ; parameters: ll hh ; pointer to subroutine ; get pointer from next 2 bytes call GetMusicByte ld e, a call GetMusicByte ld d, a push de ; copy MusicAddress to LastMusicAddress ld hl, Channel1MusicAddress - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ld hl, Channel1LastMusicAddress - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ; load pointer into MusicAddress pop de ld hl, Channel1MusicAddress - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ; set subroutine flag ld hl, Channel1Flags - Channel1 add hl, bc set 1, [hl] ret ; e87bc MusicFC: ; e87bc ; jump ; parameters: ll hh ; pointer ; get pointer from next 2 bytes call GetMusicByte ld e, a call GetMusicByte ld d, a ld hl, Channel1MusicAddress - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ret ; e87cc MusicFD: ; e87cc ; loops xx - 1 times ; 00: infinite ; params: 3 ; xx ll hh ; xx : loop count ; ll hh : pointer ; get loop count call GetMusicByte ld hl, Channel1Flags - Channel1 add hl, bc bit 2, [hl] ; has the loop been initiated? jr nz, .checkloop and a ; loop counter 0 = infinite jr z, .loop ; initiate loop dec a set 2, [hl] ; set loop flag ld hl, Channel1LoopCount - Channel1 add hl, bc ld [hl], a ; store loop counter .checkloop ld hl, Channel1LoopCount - Channel1 add hl, bc ld a, [hl] and a ; are we done? jr z, .endloop dec [hl] .loop ; get pointer call GetMusicByte ld e, a call GetMusicByte ld d, a ; load new pointer into MusicAddress ld hl, Channel1MusicAddress - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ret .endloop ; reset loop flag ld hl, Channel1Flags - Channel1 add hl, bc res 2, [hl] ; skip to next command ld hl, Channel1MusicAddress - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] inc de ; skip inc de ; pointer ld [hl], d dec hl ld [hl], e ret ; e880e MusicFA: ; e880e ; set condition for a jump ; used with FB ; params: 1 ; xx ; condition ; set condition call GetMusicByte ld hl, Channel1Condition - Channel1 add hl, bc ld [hl], a ret ; e8817 MusicFB: ; e8817 ; conditional jump ; used with FA ; params: 3 ; xx: condition ; ll hh: pointer ; check condition ; a = condition call GetMusicByte ; if existing condition matches, jump to new address ld hl, Channel1Condition - Channel1 add hl, bc cp [hl] jr z, .jump ; skip to next command ; get address ld hl, Channel1MusicAddress - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ; skip pointer inc de inc de ; update address ld [hl], d dec hl ld [hl], e ret .jump ; jump to the new address ; get pointer call GetMusicByte ld e, a call GetMusicByte ld d, a ; update pointer in MusicAddress ld hl, Channel1MusicAddress - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ret ; e883e MusicEE; e883e ; conditional jump ; checks a byte in ram corresponding to the current channel ; doesn't seem to be set by any commands ; params: 2 ; ll hh ; pointer ; if ????, jump ; get channel ld a, [CurChannel] and a, $03 ; ch0-3 ld e, a ld d, $00 ; hl = $c2b8 + channel id ld hl, $c2b8 add hl, de ; if set, jump ld a, [hl] and a jr nz, .jump ; skip to next command ; get address ld hl, Channel1MusicAddress - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ; skip pointer inc de inc de ; update address ld [hl], d dec hl ld [hl], e ret .jump ; reset jump flag ld [hl], $00 ; de = pointer call GetMusicByte ld e, a call GetMusicByte ld d, a ; update address ld hl, Channel1MusicAddress - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ret ; e886d MusicF9: ; e886d ; sets some flag ; seems to be unused ; params: 0 ld a, $01 ld [$c2b5], a ret ; e8873 MusicE2: ; e8873 ; seems to have been dummied out ; params: 1 call GetMusicByte ld hl, $002c add hl, bc ld [hl], a ld hl, Channel1Flags2 - Channel1 add hl, bc set 3, [hl] ret ; e8882 MusicE1: ; e8882 ; vibrato ; params: 2 ; 1: [xx] ; delay in frames ; 2: [yz] ; y: extent ; z: rate (# frames per cycle) ; set vibrato flag? ld hl, Channel1Flags2 - Channel1 add hl, bc set 0, [hl] ; start at lower frequency (extent is positive) ld hl, Channel1Flags3 - Channel1 add hl, bc res 0, [hl] ; get delay call GetMusicByte ; update delay ld hl, Channel1VibratoDelay - Channel1 add hl, bc ld [hl], a ; update delay count ld hl, Channel1VibratoDelayCount - Channel1 add hl, bc ld [hl], a ; update extent ; this is split into halves only to get added back together at the last second ; get extent/rate call GetMusicByte ld hl, Channel1VibratoExtent - Channel1 add hl, bc ld d, a ; get top nybble and a, $f0 swap a srl a ; halve ld e, a adc a, $00 ; round up swap a or e ld [hl], a ; update rate ld hl, Channel1VibratoRate - Channel1 add hl, bc ; get bottom nybble ld a, d and a, $0f ld d, a swap a or d ld [hl], a ret ; e88bd MusicE0: ; e88bd ; ???? ; params: 2 call GetMusicByte ld [$c297], a call GetMusicByte ld d, a and a, $0f ld e, a ld a, d swap a and a, $0f ld d, a call GetFrequency ld hl, $0021 add hl, bc ld [hl], e ld hl, $0022 add hl, bc ld [hl], d ld hl, Channel1Flags2 - Channel1 add hl, bc set 1, [hl] ret ; e88e4 MusicE6: ; e88e4 ; tone ; params: 2 ld hl, Channel1Flags2 - Channel1 add hl, bc set 4, [hl] ld hl, $0028 add hl, bc call GetMusicByte ld [hld], a call GetMusicByte ld [hl], a ret ; e88f7 MusicE7: ; e88f7 ; shrug ; params: 1 ld hl, Channel1Flags2 - Channel1 add hl, bc set 6, [hl] call GetMusicByte ld hl, $0029 add hl, bc ld [hl], a ret ; e8906 MusicDE: ; e8906 ; ???? + duty cycle ; params: 1 ; ld hl, Channel1Flags2 - Channel1 add hl, bc set 2, [hl] ; duty cycle ; call GetMusicByte rrca rrca ld hl, $001c add hl, bc ld [hl], a ; update duty cycle and a, $c0 ; only uses top 2 bits ld hl, Channel1DutyCycle - Channel1 add hl, bc ld [hl], a ret ; e891e MusicE8: ; e891e ; shrug ; params: 1 ld hl, Channel1Flags2 - Channel1 add hl, bc set 5, [hl] call GetMusicByte ld hl, $002a add hl, bc ld [hl], a ret ; e892d MusicDF: ; e892d ; toggle something ; params: none ld hl, Channel1Flags - Channel1 add hl, bc bit 3, [hl] jr z, .on res 3, [hl] ret .on set 3, [hl] ret ; e893b MusicE3: ; e893b ; toggle music noise sampling ; can't be used as a straight toggle since the param is not read from on->off ; params: ; noise on: 1 ; noise off: 0 ; check if noise sampling is on ld hl, Channel1Flags - Channel1 add hl, bc bit 4, [hl] jr z, .on ; turn noise sampling off res 4, [hl] ret .on ; turn noise sampling on set 4, [hl] call GetMusicByte ld [MusicNoiseSampleSet], a ret ; e894f MusicF0: ; e894f ; toggle sfx noise sampling ; params: ; on: 1 ; off: 0 ; check if noise sampling is on ld hl, Channel1Flags - Channel1 add hl, bc bit 4, [hl] jr z, .on ; turn noise sampling off res 4, [hl] ret .on ; turn noise sampling on set 4, [hl] call GetMusicByte ld [SFXNoiseSampleSet], a ret ; e8963 MusicD8: ; e8963 ; note length ; # frames per 16th note ; intensity: see MusicDC ; params: 2 ; note length call GetMusicByte ld hl, $002d add hl, bc ld [hl], a ld a, [CurChannel] and a, $03 cp a, $03 ret z ; intensity call MusicDC ret ; e8977 MusicDD: ; e8977 ; update sound status ; params: 1 call GetMusicByte ld [SoundInput], a ld hl, Channel1NoteFlags - Channel1 add hl, bc set 3, [hl] ret ; e8984 MusicDB: ; e8984 ; duty cycle ; params: 1 call GetMusicByte rrca rrca and a, $c0 ld hl, Channel1DutyCycle - Channel1 add hl, bc ld [hl], a ret ; e8991 MusicDC: ; e8991 ; intensity ; params: 1 ; hi: pressure ; lo: velocity call GetMusicByte ld hl, Channel1Intensity - Channel1 add hl, bc ld [hl], a ret ; e899a MusicDA: ; e899a ; global tempo ; params: 2 ; de: tempo call GetMusicByte ld d, a call GetMusicByte ld e, a call SetGlobalTempo ret ; e89a6 MusicD0: ; e89a6 ; used by d0-d7 ; set octave based on lo nybble of the command ld hl, Channel1Octave - Channel1 add hl, bc ld a, [CurMusicByte] ; get current command and a, $07 ld [hl], a ret ; e89b1 MusicD9: ; e89b1 ; set starting octave ; this forces all notes up by the starting octave ; params: 1 call GetMusicByte ld hl, Channel1StartingOctave - Channel1 add hl, bc ld [hl], a ret ; e89ba MusicEF: ; e89ba ; stereo panning ; params: 1 ; stereo on? ld a, [Options] bit 5, a ; stereo jr nz, MusicE4 ; skip param call GetMusicByte ret ; e89c5 MusicE4: ; e89c5 ; force panning ; params: 1 call SetLRTracks call GetMusicByte ld hl, Channel1Tracks - Channel1 add hl, bc and [hl] ld [hl], a ret ; e89d2 MusicE5: ; e89d2 ; set volume ; params: 1 ; see Volume ; read param even if it's not used call GetMusicByte ; is the song fading? ld a, [MusicFade] and a ret nz ; reload param ld a, [CurMusicByte] ; set volume ld [Volume], a ret ; e89e1 MusicE9: ; e89e1 ; set global tempo to current channel tempo +- param ; params: 1 signed call GetMusicByte ld e, a ; check sign cp a, $80 jr nc, .negative ;positive ld d, $00 jr .ok .negative ld d, $ff .ok ld hl, Channel1Tempo - Channel1 add hl, bc ld a, [hli] ld h, [hl] ld l, a add hl, de ld e, l ld d, h call SetGlobalTempo ret ; e89fd MusicEC: ; e89fd ; turn sfx priority on ; params: none ld a, $01 ld [SFXPriority], a ret ; e8a03 MusicED: ; e8a03 ; turn sfx priority off ; params: none xor a ld [SFXPriority], a ret ; e8a08 MusicEA: ; e8a08 ; restart current channel from channel header (same bank) ; params: 2 (5) ; ll hh: pointer to new channel header ; header format: 0x yy zz ; x: channel # (0-3) ; zzyy: pointer to new music data ; update music id ld hl, Channel1MusicID - Channel1 add hl, bc ld a, [hli] ld [MusicIDLo], a ld a, [hl] ld [MusicIDHi], a ; update music bank ld hl, Channel1MusicBank - Channel1 add hl, bc ld a, [hl] ld [MusicBank], a ; get pointer to new channel header call GetMusicByte ld l, a call GetMusicByte ld h, a ld e, [hl] inc hl ld d, [hl] push bc ; save current channel call LoadChannel call StartChannel pop bc ; restore current channel ret ; e8a30 MusicEB: ; e8a30 ; new song ; params: 2 ; de: song id call GetMusicByte ld e, a call GetMusicByte ld d, a push bc call LoadMusic pop bc ret ; e8a3e GetMusicByte: ; e8a3e ; returns byte from current address in a ; advances to next byte in music data ; input: bc = start of current channel push hl push de ; load address into de ld hl, Channel1MusicAddress - Channel1 add hl, bc ld a, [hli] ld e, a ld d, [hl] ; load bank into a ld hl, Channel1MusicBank - Channel1 add hl, bc ld a, [hl] ; get byte call LoadMusicByte ; load data into CurMusicByte inc de ; advance to next byte for next time this is called ; update channeldata address ld hl, Channel1MusicAddress - Channel1 add hl, bc ld a, e ld [hli], a ld [hl], d ; cleanup pop de pop hl ; store channeldata in a ld a, [CurMusicByte] ret ; e8a5d GetFrequency: ; e8a5d ; generate frequency ; input: ; d: octave ; e: pitch ; output: ; de: frequency ; get octave ; get starting octave ld hl, Channel1StartingOctave - Channel1 add hl, bc ld a, [hl] swap a ; hi nybble and a, $0f ; add current octave add d push af ; we'll use this later ; get starting octave ld hl, Channel1StartingOctave - Channel1 add hl, bc ld a, [hl] and a, $0f ; lo nybble ; ld l, a ; ok ld d, $00 ld h, d add hl, de ; add current pitch add hl, hl ; skip 2 bytes for each ld de, FrequencyTable add hl, de ld e, [hl] inc hl ld d, [hl] ; get our octave pop af .loop ; [7 - octave] loops cp a, $07 jr nc, .ok ; sra de sra d rr e inc a jr .loop .ok ld a, d and a, $07 ; top 3 bits for frequency (11 total) ld d, a ret ; e8a8d SetNoteDuration: ; e8a8d ; input: a = note duration in 16ths ; store delay units in de inc a ld e, a ld d, $00 ; store NoteLength in a ld hl, Channel1NoteLength - Channel1 add hl, bc ld a, [hl] ; multiply NoteLength by delay units ld l, $00 ; just multiply call MultiplySimple ld a, l ; % $100 ; store Tempo in de ld hl, Channel1Tempo - Channel1 add hl, bc ld e, [hl] inc hl ld d, [hl] ; add ???? to the next result ld hl, $0016 add hl, bc ld l, [hl] ; multiply Tempo by last result (NoteLength * delay % $100) call MultiplySimple ; copy result to de ld e, l ld d, h ; store result in ???? ld hl, $0016 add hl, bc ld [hl], e ; store result in NoteDuration ld hl, Channel1NoteDuration - Channel1 add hl, bc ld [hl], d ret ; e8ab8 MultiplySimple: ; e8ab8 ; multiplies a and de ; adds the result to l ; stores the result in hl ld h, $00 .loop ; halve a srl a ; is there a remainder? jr nc, .skip ; add it to the result add hl, de .skip ; add de, de sla e rl d ; are we done? and a jr nz, .loop ret ; e8ac7 SetGlobalTempo: ; e8ac7 push bc ; save current channel ; are we dealing with music or sfx? ld a, [CurChannel] cp a, $04 jr nc, .sfxchannels ld bc, Channel1 call SetTempo ld bc, Channel2 call SetTempo ld bc, Channel3 call SetTempo ld bc, Channel4 call SetTempo jr .end .sfxchannels ld bc, Channel5 call SetTempo ld bc, Channel6 call SetTempo ld bc, Channel7 call SetTempo ld bc, Channel8 call SetTempo .end pop bc ; restore current channel ret ; e8b03 SetTempo: ; e8b03 ; input: ; de: note length ; update Tempo ld hl, Channel1Tempo - Channel1 add hl, bc ld [hl], e inc hl ld [hl], d ; clear ???? xor a ld hl, $0016 add hl, bc ld [hl], a ret ; e8b11 StartChannel: ; e8b11 call SetLRTracks ld hl, Channel1Flags - Channel1 add hl, bc set 0, [hl] ; turn channel on ret ; e8b1b SetLRTracks: ; e8b1b ; set tracks for a the current channel to default ; seems to be redundant since this is overwritten by stereo data later push de ; store current channel in de ld a, [CurChannel] and a, $03 ld e, a ld d, $00 ; get this channel's lr tracks call GetLRTracks add hl, de ; de = channel 0-3 ld a, [hl] ; load lr tracks into Tracks ld hl, Channel1Tracks - Channel1 add hl, bc ld [hl], a pop de ret ; e8b30 LoadMusic: ; e8b30 ; load music call MusicOff ld hl, MusicID ld [hl], e ; song number inc hl ld [hl], d ; MusicIDHi (always $00) ld hl, Music add hl, de ; three add hl, de ; byte add hl, de ; pointer ld a, [hli] ld [MusicBank], a ld e, [hl] inc hl ld d, [hl] ; music header address call FarLoadMusicByte ; store first byte of music header in a rlca rlca and a, $03 ; get number of channels inc a .loop ; start playing channels push af call LoadChannel call StartChannel pop af dec a jr nz, .loop xor a ld [$c2b5], a ld [$c2b8], a ld [$c2b9], a ld [$c2ba], a ld [$c2bb], a ld [NoiseSampleAddressLo], a ld [NoiseSampleAddressHi], a ld [$c2a2], a ld [MusicNoiseSampleSet], a call MusicOn ret ; e8b79 PlayCry: ; e8b79 ; Play cry de using parameters: ; CryPitch ; CryEcho ; CryLength call MusicOff ; Overload the music id with the cry id ld hl, MusicID ld [hl], e inc hl ld [hl], d ; 3-byte pointers (bank, address) ld hl, Cries add hl, de add hl, de add hl, de ld a, [hli] ld [MusicBank], a ld e, [hl] inc hl ld d, [hl] ; Read the cry's sound header call FarLoadMusicByte ; Top 2 bits contain the number of channels rlca rlca and a, 3 ; For each channel: inc a .loop push af call LoadChannel ld hl, Channel1Flags - Channel1 add hl, bc set 5, [hl] ld hl, Channel1Flags2 - Channel1 add hl, bc set 4, [hl] ld hl, Channel1CryPitch - Channel1 add hl, bc ld a, [CryPitch] ld [hli], a ld a, [CryEcho] ld [hl], a ; No tempo for channel 4 ld a, [CurChannel] and a, 3 cp 3 jr nc, .start ; Tempo is effectively length ld hl, Channel1Tempo - Channel1 add hl, bc ld a, [CryLength] ld [hli], a ld a, [CryLength+1] ld [hl], a .start call StartChannel ld a, [$c2bc] and a jr z, .next ; Stereo only: Play cry from the monster's side. ; This only applies in-battle. ld a, [Options] bit 5, a ; stereo jr z, .next ; [Tracks] &= [CryTracks] ld hl, Channel1Tracks - Channel1 add hl, bc ld a, [hl] ld hl, CryTracks and a, [hl] ld hl, Channel1Tracks - Channel1 add hl, bc ld [hl], a .next pop af dec a jr nz, .loop ; Cries play at max volume, so we save the current volume for later. ld a, [LastVolume] and a jr nz, .end ld a, [Volume] ld [LastVolume], a ld a, $77 ld [Volume], a .end ld a, 1 ; stop playing music ld [SFXPriority], a call MusicOn ret ; e8c04 LoadSFX: ; e8c04 ; clear channels if they aren't already call MusicOff ld hl, $c1cc ; Channel5Flags bit 0, [hl] ; ch5 on? jr z, .ch6 res 0, [hl] ; turn it off xor a ld [rNR11], a ; length/wavepattern = 0 ld a, $08 ld [rNR12], a ; envelope = 0 xor a ld [rNR13], a ; frequency lo = 0 ld a, $80 ld [rNR14], a ; restart sound (freq hi = 0) xor a ld [SoundInput], a ; global sound off ld [rNR10], a ; sweep = 0 .ch6 ld hl, $c1fe ; ch6 on? bit 0, [hl] jr z, .ch7 res 0, [hl] ; turn it off xor a ld [rNR21], a ; length/wavepattern = 0 ld a, $08 ld [rNR22], a ; envelope = 0 xor a ld [rNR23], a ; frequency lo = 0 ld a, $80 ld [rNR24], a ; restart sound (freq hi = 0) .ch7 ld hl, $c230 ; ch7 on? bit 0, [hl] jr z, .ch8 res 0, [hl] ; turn it off xor a ld [rNR30], a ; sound mode #3 off ld [rNR31], a ; length/wavepattern = 0 ld a, $08 ld [rNR32], a ; envelope = 0 xor a ld [rNR33], a ; frequency lo = 0 ld a, $80 ld [rNR34], a ; restart sound (freq hi = 0) .ch8 ld hl, $c262 ; ch8 on? bit 0, [hl] jr z, .chscleared res 0, [hl] ; turn it off xor a ld [rNR41], a ; length/wavepattern = 0 ld a, $08 ld [rNR42], a ; envelope = 0 xor a ld [rNR43], a ; frequency lo = 0 ld a, $80 ld [rNR44], a ; restart sound (freq hi = 0) xor a ld [NoiseSampleAddressLo], a ld [NoiseSampleAddressHi], a .chscleared ; start reading sfx header for # chs ld hl, MusicID ld [hl], e inc hl ld [hl], d ld hl, SFX add hl, de ; three add hl, de ; byte add hl, de ; pointers ; get bank ld a, [hli] ld [MusicBank], a ; get address ld e, [hl] inc hl ld d, [hl] ; get # channels call FarLoadMusicByte rlca ; top 2 rlca ; bits and a, $03 inc a ; # channels -> # loops .startchannels push af call LoadChannel ; bc = current channel ld hl, Channel1Flags - Channel1 add hl, bc set 3, [hl] call StartChannel pop af dec a jr nz, .startchannels call MusicOn xor a ld [SFXPriority], a ret ; e8ca6 PlaySFX: ; e8ca6 ; play sfx de call MusicOff ; standard procedure if stereo's off ld a, [Options] bit 5, a jp z, LoadSFX ; else, let's go ahead with this ld hl, MusicID ld [hl], e inc hl ld [hl], d ; get sfx ptr ld hl, SFX add hl, de add hl, de add hl, de ; bank ld a, [hli] ld [MusicBank], a ; address ld e, [hl] inc hl ld d, [hl] ; bit 2-3 call FarLoadMusicByte rlca rlca and 3 ; ch1-4 inc a .loop push af call LoadChannel ld hl, Channel1Flags - Channel1 add hl, bc set 3, [hl] push de ; get tracks for this channel ld a, [CurChannel] and 3 ; ch1-4 ld e, a ld d, $0 call GetLRTracks add hl, de ld a, [hl] ld hl, $c2bc and [hl] ld hl, Channel1Tracks - Channel1 add hl, bc ld [hl], a ld hl, $0030 ; $c131 - Channel1 add hl, bc ld [hl], a ld a, [CryTracks] cp 2 ; ch 1-2 jr c, .asm_e8d0c ; ch3-4 ld a, [$c2be] ld hl, $002e ; $c12f - Channel1 add hl, bc ld [hl], a ld hl, $002f ; $c130 - Channel1 add hl, bc ld [hl], a ld hl, Channel1Flags2 - Channel1 add hl, bc set 7, [hl] .asm_e8d0c pop de ; turn channel on ld hl, Channel1Flags - Channel1 add hl, bc set 0, [hl] ; on ; done? pop af dec a jr nz, .loop ; we're done call MusicOn ret ; e8d1b LoadChannel: ; e8d1b ; prep channel for use ; input: ; de: ; get pointer to current channel call FarLoadMusicByte inc de and a, $07 ; bit 0-2 (current channel) ld [CurChannel], a ld c, a ld b, $00 ld hl, ChannelPointers add hl, bc add hl, bc ld c, [hl] inc hl ld b, [hl] ; bc = channel pointer ld hl, Channel1Flags - Channel1 add hl, bc res 0, [hl] ; channel off call ChannelInit ; load music pointer ld hl, Channel1MusicAddress - Channel1 add hl, bc call FarLoadMusicByte ld [hli], a inc de call FarLoadMusicByte ld [hl], a inc de ; load music id ld hl, Channel1MusicID - Channel1 add hl, bc ld a, [MusicIDLo] ld [hli], a ld a, [MusicIDHi] ld [hl], a ; load music bank ld hl, Channel1MusicBank - Channel1 add hl, bc ld a, [MusicBank] ld [hl], a ret ; e8d5b ChannelInit: ; e8d5b ; make sure channel is cleared ; set default tempo and note length in case nothing is loaded ; input: ; bc = channel struct pointer push de xor a ; get channel struct location and length ld hl, Channel1MusicID - Channel1 ; start add hl, bc ld e, Channel2 - Channel1 ; channel struct length ; clear channel .loop ld [hli], a dec e jr nz, .loop ; set tempo to default ($100) ld hl, Channel1Tempo - Channel1 add hl, bc xor a ld [hli], a inc a ld [hl], a ; set note length to default ($01) (fast) ld hl, Channel1NoteLength - Channel1 add hl, bc ld [hl], a pop de ret ; e8d76 FarLoadMusicByte: ; e8d76 ; input: ; de = current music address ; output: ; a = CurMusicByte ld a, [MusicBank] call LoadMusicByte ld a, [CurMusicByte] ret ; e8d80 FrequencyTable: ; e8d80 dw $0000 ; filler dw $f82c dw $f89d dw $f907 dw $f96b dw $f9ca dw $fa23 dw $fa77 dw $fac7 dw $fb12 dw $fb58 dw $fb9b dw $fbda dw $fc16 dw $fc4e dw $fc83 dw $fcb5 dw $fce5 dw $fd11 dw $fd3b dw $fd63 dw $fd89 dw $fdac dw $fdcd dw $fded ; e8db2 WaveSamples: ; e8db2 ; these are streams of 32 4-bit values used as wavepatterns ; nothing interesting here! db $02, $46, $8a, $ce, $ff, $fe, $ed, $dc, $cb, $a9, $87, $65, $44, $33, $22, $11 db $02, $46, $8a, $ce, $ef, $ff, $fe, $ee, $dd, $cb, $a9, $87, $65, $43, $22, $11 db $13, $69, $bd, $ee, $ee, $ff, $ff, $ed, $de, $ff, $ff, $ee, $ee, $db, $96, $31 db $02, $46, $8a, $cd, $ef, $fe, $de, $ff, $ee, $dc, $ba, $98, $76, $54, $32, $10 db $01, $23, $45, $67, $8a, $cd, $ee, $f7, $7f, $ee, $dc, $a8, $76, $54, $32, $10 db $00, $11, $22, $33, $44, $33, $22, $11, $ff, $ee, $cc, $aa, $88, $aa, $cc, $ee db $02, $46, $8a, $ce, $cb, $a9, $87, $65, $ff, $fe, $ed, $dc, $44, $33, $22, $11 db $c0, $a9, $87, $f5, $ff, $fe, $ed, $dc, $44, $33, $22, $f1, $02, $46, $8a, $ce db $44, $33, $22, $1f, $00, $46, $8a, $ce, $f8, $fe, $ed, $dc, $cb, $a9, $87, $65 db $11, $00, $00, $08, $00, $13, $57, $9a, $b4, $ba, $a9, $98, $87, $65, $43, $21 ; e8e52 NoiseSampleSetsPointers: ; e8e52 dw NoiseSampleSets0 dw NoiseSampleSets1 dw NoiseSampleSets2 dw NoiseSampleSets3 dw NoiseSampleSets4 dw NoiseSampleSets5 ; e8e5e NoiseSampleSets: NoiseSampleSets0: ; e8e5e dw NoiseSampleSet00 ; rest dw NoiseSampleSet01 ; c dw NoiseSampleSet02 ; c# dw NoiseSampleSet03 ; d dw NoiseSampleSet04 ; d# dw NoiseSampleSet05 ; e dw NoiseSampleSet06 ; f dw NoiseSampleSet07 ; f# dw NoiseSampleSet08 ; g dw NoiseSampleSet09 ; g# dw NoiseSampleSet10 ; a dw NoiseSampleSet11 ; a# dw NoiseSampleSet12 ; b NoiseSampleSets1: ; e8e78 dw NoiseSampleSet00 dw NoiseSampleSet08 dw NoiseSampleSet09 dw NoiseSampleSet10 dw NoiseSampleSet11 dw NoiseSampleSet12 dw NoiseSampleSet13 dw NoiseSampleSet14 dw NoiseSampleSet15 dw NoiseSampleSet16 dw NoiseSampleSet17 dw NoiseSampleSet18 dw NoiseSampleSet19 NoiseSampleSets2: ; e8e92 dw NoiseSampleSet00 dw NoiseSampleSet01 dw NoiseSampleSet17 dw NoiseSampleSet18 dw NoiseSampleSet19 dw NoiseSampleSet05 dw NoiseSampleSet06 dw NoiseSampleSet07 dw NoiseSampleSet08 dw NoiseSampleSet09 dw NoiseSampleSet10 dw NoiseSampleSet11 dw NoiseSampleSet12 NoiseSampleSets3: ; e8eac dw NoiseSampleSet21 dw NoiseSampleSet22 dw NoiseSampleSet23 dw NoiseSampleSet24 dw NoiseSampleSet25 dw NoiseSampleSet26 dw NoiseSampleSet20 dw NoiseSampleSet27 dw NoiseSampleSet28 dw NoiseSampleSet29 dw NoiseSampleSet21 dw NoiseSampleSet37 dw NoiseSampleSet34 NoiseSampleSets4: ; e8ec6 dw NoiseSampleSet21 dw NoiseSampleSet20 dw NoiseSampleSet23 dw NoiseSampleSet24 dw NoiseSampleSet25 dw NoiseSampleSet33 dw NoiseSampleSet26 dw NoiseSampleSet35 dw NoiseSampleSet31 dw NoiseSampleSet32 dw NoiseSampleSet36 dw NoiseSampleSet37 dw NoiseSampleSet30 NoiseSampleSets5: ; e8ee0 dw NoiseSampleSet00 dw NoiseSampleSet17 dw NoiseSampleSet18 dw NoiseSampleSet19 dw NoiseSampleSet27 dw NoiseSampleSet28 dw NoiseSampleSet29 dw NoiseSampleSet05 dw NoiseSampleSet06 dw NoiseSampleSet30 dw NoiseSampleSet24 dw NoiseSampleSet23 dw NoiseSampleSet37 ; e8efa NoiseSampleSet00: ; e8efa ; unused db $20, $11, $00 db $ff ; end ; e8efe NoiseSampleSet01: ; e8efe db $20, $c1, $33 db $ff ; end ; e8f02 NoiseSampleSet02: ; e8f02 db $20, $b1, $33 db $ff ; end ; e8f06 NoiseSampleSet03: ; e8f06 db $20, $a1, $33 db $ff ; end ; e8f0a NoiseSampleSet04: ; e8f0a db $20, $81, $33 db $ff ; end ; e8f0e NoiseSampleSet05: ; e8f0e db $27, $84, $37 db $26, $84, $36 db $25, $83, $35 db $24, $83, $34 db $23, $82, $33 db $22, $81, $32 db $ff ; end ; e8f21 NoiseSampleSet06: ; e8f21 db $20, $51, $2a db $ff ; end ; e8f25 NoiseSampleSet07: ; e8f25 db $21, $41, $2b db $20, $61, $2a db $ff ; end ; e8f2c NoiseSampleSet08: ; e8f2c db $20, $81, $10 db $ff ; end ; e8f30 NoiseSampleSet09: ; e8f30 db $20, $82, $23 db $ff ; end ; e8f34 NoiseSampleSet10: ; e8f34 db $20, $82, $25 db $ff ; end ; e8f38 NoiseSampleSet11: ; e8f38 db $20, $82, $26 db $ff ; end ; e8f3c NoiseSampleSet12: ; e8f3c db $20, $a1, $10 db $ff ; end ; e8f40 NoiseSampleSet13: ; e8f40 db $20, $a2, $11 db $ff ; end ; e8f44 NoiseSampleSet14: ; e8f44 db $20, $a2, $50 db $ff ; end ; e8f48 NoiseSampleSet15: ; e8f48 db $20, $a1, $18 db $20, $31, $33 db $ff ; end ; e8f4f NoiseSampleSet16: ; e8f4f db $22, $91, $28 db $20, $71, $18 db $ff ; end ; e8f56 NoiseSampleSet17: ; e8f56 db $20, $91, $22 db $ff ; end ; e8f5a NoiseSampleSet18: ; e8f5a db $20, $71, $22 db $ff ; end ; e8f5e NoiseSampleSet19: ; e8f5e db $20, $61, $22 db $ff ; end ; e8f62 NoiseSampleSet20: ; e8f62 db $20, $11, $11 db $ff ; end ; e8f66 NoiseSampleSet21: ; e8f66 db $ff ; e8f67 NoiseSampleSet22: ; e8f67 db $20, $91, $33 db $ff ; end ; e8f6b NoiseSampleSet23: ; e8f6b db $20, $51, $32 db $ff ; end ; e8f6f NoiseSampleSet24: ; e8f6f db $20, $81, $31 db $ff ; end ; e8f73 NoiseSampleSet25: ; e8f73 db $20, $88, $6b db $20, $71, $00 db $ff ; end ; e8f7a NoiseSampleSet26: ; e8f7a db $30, $91, $18 db $ff ; end ; e8f7e NoiseSampleSet27: ; e8f7e db $27, $92, $10 db $ff ; end ; e8f82 NoiseSampleSet28: ; e8f82 db $33, $91, $00 db $33, $11, $00 db $ff ; end ; e8f89 NoiseSampleSet29: ; e8f89 db $33, $91, $11 db $33, $11, $00 db $ff ; end ; e8f90 NoiseSampleSet30: ; e8f90 db $33, $88, $15 db $20, $65, $12 db $ff ; end ; e8f97 NoiseSampleSet31: ; e8f97 db $33, $51, $21 db $33, $11, $11 db $ff ; end ; e8f9e NoiseSampleSet32: ; e8f9e db $33, $51, $50 db $33, $11, $11 db $ff ; end ; e8fa5 NoiseSampleSet33: ; e8fa5 db $20, $a1, $31 db $ff ; end ; e8fa9 NoiseSampleSet34: ; e8fa9 db $20, $84, $12 db $ff ; end ; e8fad NoiseSampleSet35: ; e8fad db $33, $81, $00 db $33, $11, $00 db $ff ; end ; e8fb4 NoiseSampleSet36: ; e8fb4 db $33, $81, $21 db $33, $11, $11 db $ff ; end ; e8fbb NoiseSampleSet37: ; e8fbb db $20, $a8, $6b db $20, $71, $00 db $ff ; end ; e8fc2 GetLRTracks: ; e8fc2 ; gets the default sound l/r channels ; stores mono/stereo table in hl ld a, [Options] bit 5, a ; stereo ; made redundant, could have had a purpose in gold jr nz, .stereo ld hl, MonoTracks ret .stereo ld hl, StereoTracks ret ; e8fd1 MonoTracks: ; e8fd1 ; bit corresponds to track # ; hi: left channel ; lo: right channel db $11, $22, $44, $88 ; e8fd5 StereoTracks: ; e8fd5 ; made redundant ; seems to be modified on a per-song basis db $11, $22, $44, $88 ; e8fd9 ChannelPointers: ; e8fd9 ; music channels dw Channel1 dw Channel2 dw Channel3 dw Channel4 ; sfx channels dw Channel5 dw Channel6 dw Channel7 dw Channel8 ; e8fe9 ClearChannels: ; e8fe9 ; runs ClearChannel for all 4 channels ; doesn't seem to be used, but functionally identical to SoundRestart ld hl, rNR50 xor a ld [hli], a ld [hli], a ld a, $80 ld [hli], a ld hl, rNR10 ld e, $04 .loop call ClearChannel dec e jr nz, .loop ret ; e8ffe ClearChannel: ; e8ffe ; input: hl = beginning hw sound register (rNR10, $ff15, rNR30, $ff1f) ; output: 00 00 80 00 80 ; sound channel 1 2 3 4 xor a ld [hli], a ; rNR10, $ff15, rNR30, $ff1f ; sweep = 0 ld [hli], a ; rNR11, rNR21, rNR31, rNR41 ; length/wavepattern = 0 ld a, $08 ld [hli], a ; rNR12, rNR22, rNR32, rNR42 ; envelope = 0 xor a ld [hli], a ; rNR13, rNR23, rNR33, rNR43 ; frequency lo = 0 ld a, $80 ld [hli], a ; rNR14, rNR24, rNR34, rNR44 ; restart sound (freq hi = 0) ret ; e900a